Brain-computer interfaces (BCIs) enable the control of a computer without muscular action. BCIs based on electroencephalography (EEG) have improved dramatically over the past five years, but their head-worn form factor and awkward visibility have challenged their wider adoption.

In these projects, we used a home-rigged, single-electrode EEG placed inside the ear canal (above) to investigate how signals from the ear could be used for “mental gestures,” and for passthought-style authentication (see our past work on passthoughts). Eventually, this research could provide hands-free interaction, authentication, and a seamless and comfortable user experience, all in the form-factor of a typical earbud.

More recently we created custom-fit earpieces with embedded electrodes and tested this paradigm, finding significant improvements in authentication accuracy compared to the single-electrode hardware. By capturing inherence and knowledge authentication factors via passthoughts, and the potential for a possession factor built in to a custom earpiece, we demonstrate a proof of concept for a highly secure and highly usable form of authentication.